The luxury goods industry loves an exotic skin. Yes, there's prosaic cow leather, but recently we've seen python, crocodile and a return to the Art Deco favourite, stingray – also known as shagreen. This is dictated by trend, but also by what manufacturers can get their hands on. That in turn is governed by the Convention on International Trade in Endangered Species (cites.org).Species falling under Appendix I, including those threatened with extinction, are out of bounds except in "exceptional circumstances" (thankfully a purse does not qualify).

I note from your email that you've written to Smythson about its use of stingray and they have replied: "In the case of animals listed in Appendix II, which includes shagreen, skins are imported into the EU accompanied by the export certificate issued by the government of the country of origin." Full marks to them for having their paperwork in order and not just fobbing you off by saying stingray is a "sustainable by-product" of fishing.

But is this a green light to use shagreen? Appendix II covers "species not necessarily threatened with extinction, but in which trade must be controlled…" Just because legally you can use a species, should you? I think luxury brands should examine their use of skins.

A UN biotrade initiative, Resp, has challenged industry assumptions around python and crocodile skins, but not fish. There's an assumption with the latter that because crocodiles are now farmed and therefore not "plundered" from the wild they can be considered sustainable. But farming them brings up animal welfare issues and doesn't always relieve the pressure on wild populations. (Insiders at Resp tell me there's a move to look at stingrays next.)

New research reveals we've been complacent about chondrichthyans (including sharks, rays and chimaeras). A recent report from the IUCN (International Union for Conservation of Nature) suggests that a quarter are actually threatened with extinction. This could be attributed to a paucity of data and the fact that stingray species can be hard to distinguish. Worryingly, a vulnerable stingray species could look similar to one categorised as being of "least concern". The freshwater Mekong stingray has experienced a population decline of 50% over the past 20 years.

You can see the appeal of using shagreen for designers. You just happen to find the real animal more beautiful, and conservation science is beginning to take your side.

Green crush

"Games for good" challenge the idea that gaming is a worthless pastime solely practised by teenagers and kidults. Without leaving your sofa, wearing a white coat or gaining a BSc, you can contribute to medical, nature or climate research (zooniverse.org) by gaming. Genes in Space, developed by Guerilla Tea in Dundee for Cancer Research, looks like a classic space invaders game, but as you steer your spaceship you're unlocking genetic data and helping the Cancer Research institute in Cambridge. So far 1.5m records have been analysed by gamers through the free app, achieving data analysis in weeks that would have taken scientists six months to get through.

Greenspeak: Stipster {ztipp-sta} noun

An elision of start-up and hipster, this applies to Scandanavian social entrepreneurs known for their eco sensitivity, commitment to innovation and co-operation – and penchant for annoying hats.